Do you actually know that BSI would give you a worthwhile improvement on a larger 1/1.7" sensor? The point of BSI is that the interconnects around the sensor pixels no-longer get in the way, and proportional these take up more space on a small 1/2.3 sensor than a larger 1/1.7 sensor.

While this may give a marginal improvement on a 1/1.7" sensor have you considered that the improvement isn't enough to justify the extra cost, hence no-one is yet offering one? I'm pretty sure there isn't some big conspiracy to keep a 1/1.7 BSI CMOS sensor out of your hands

I have heard of the diminishing returns as this technology is scaled up, so I am not sure if the gain will be there, not until a camera is produced. I never even imagined that there was a conspiracy, only market forces at work.

I already have a premium compact with a 1/1.7 CCD, what I am talking about is a future one using 1/1.7 BSI-CMOS. The feature search of this site shows that such a camera doesn't exist, the closest is the canon S100 which is CMOS but not backlit. The 1/2.3 BSI-CMOS sensors are giving about the same high ISO performance as the 1/1.7 CCD, example like the canon SX240HS show this, so it is possible that if the sensor could be scaled up then there would be a performance gain for the enthusiast class of camera. My concern is that this may never be made.

Most responders in this thread have jumped to the conclusion that I am trying to limit what they can buy, but they can buy what they need, I am only talking about what I want. For those that can understand english please do not twist around what I am saying.

By the way, this last paragraph wasn't about you.

My point was that most of what you want is available, but your perfect camera (pocketable 1/1.7" 10x zoom) isn't practical. Not sure why you're so hung-up on a BSI sensor, I'm sure if it's worthwhile for 1/1.7 sensors it will be used.

I already own a CCD based EX1 with 24-72mm, and it would be nice to have the same performance in a slightly smaller package and with a bit more zoom. I don't want the current batch of 1000mm super zooms based on the 1/2.3 BSI-CMOS, as someone has already pointed out the lens performance suffers too much. I have been thinking that a good step forward from where pocketable enthusiast camera are currently could be achieved using BSI-CMOS. The reason why I would like to see the larger BSI made is because based on the smaller one it looks like cleaner higher ISO may be achievable. If it doesn't happen then it won't be the end of the world as far as I am concerned.

You want both a large/wide zoom range and a larger sensor in a compact body? Can't be done, a larger sensor requires either a physically larger lens (which you don't want) or a smaller max aperture, which negates most the advantages of the larger sensor anyway.

I agree, so far existing long zoom models have often used apertures as small as f3.5 where I want at least f1.8

If you want
pocketable
then you can have either a fast limited zoom like the f1.8-2.5 4x zoom on the Olympus XZ-1 or a slower long 10-12x zoom. You can't have both, that's just the laws of physics. Hypothetical designs such as liquid lenses might be able to deliver this, but we're going to have to wait for those

I've already owned the equivalent for two years now, it would be nice to see an upgrade path.